If you have the budget, SQL BackTrack from BMC provides for hot backup
(and incremental with tablespace restores) of your Oracle DB.  That will
provide some relief for your tight backup window.  The software also has
a dry run  feature that can help validate the consistency of your backup
and restores. There is also a guided recovery tool that eases the
administration of complex restores.  It knows in what order to apply the
redo logs.  If you have questions feel free to contact me.

Regards,
Eric P. Gruber
ADSM Certified Instructor/Consultant
RISCmanagement, Inc.
egruber AT riscman DOT com

                -----Original Message-----
                From:   ADSM: Dist Stor Manager
[mailto:ADSM-L AT VM.MARIST DOT EDU] On Behalf Of Kauffman, Tom
                Sent:   Monday, February 22, 1999 6:06 PM
                To:     ADSM-L AT VM.MARIST DOT EDU
                Subject:        How do you handle time-critical backups?

                I just ran into an ugly situation this weekend. We
restored our production
                Oracle database to a test server -- and hit a read error
on one of the five
                DLT tapes (about 60 GB on each tape). I ended up
re-trying this tape on all
                drives, to no avail. And, of course, without the 9.2 GB
that failed, the
                entire database was unusable.

                There were *no* errors logged when the tape was created.

                It takes about 4.5 hours to run the backup; I get one
12-hour window per
                week for an off-line (and the bulk of the 12-hour window
is dedicated to OS
                upgrades, Oracle reorgs, and anything else that may
require a shutdown).

                How do I avoid this problem in the future? Is there
*any* platform which
                supports dual-write or mirrored tape (I could do this on
GCOS-3 15 years ago
                . . .)?

                Ideally, I'd like to verify the validity of the backup
before turning the
                system over to anyone else - but the window just isn't
there (we don't even
                have enough window to copy this -- the originals are
marked 'unavailable'
                and shipped off-site).

                TIA

                Tom Kauffman
                Sr. Technical Analyst
                NIBCO, Inc.